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    Physics General Subjects Thread

    Sprut-B
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    Post  Sprut-B Sat Oct 01, 2022 4:41 pm

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    Post  kvs Wed Jan 25, 2023 12:09 am

    https://news.mit.edu/2023/roman-concrete-durability-lime-casts-0106

    Riddle solved: Why was Roman concrete so durable?

    The ancient Romans were masters of engineering, constructing vast networks of roads, aqueducts, ports, and massive buildings, whose remains have survived for two millennia. Many of these structures were built with concrete: Rome’s famed Pantheon, which has the world’s largest unreinforced concrete dome and was dedicated in A.D. 128, is still intact, and some ancient Roman aqueducts still deliver water to Rome today. Meanwhile, many modern concrete structures have crumbled after a few decades.

    Researchers have spent decades trying to figure out the secret of this ultradurable ancient construction material, particularly in structures that endured especially harsh conditions, such as docks, sewers, and seawalls, or those constructed in seismically active locations.

    Now, a team of investigators from MIT, Harvard University, and laboratories in Italy and Switzerland, has made progress in this field, discovering ancient concrete-manufacturing strategies that incorporated several key self-healing functionalities. The findings are published today in the journal Science Advances, in a paper by MIT professor of civil and environmental engineering Admir Masic, former doctoral student Linda Seymour ’14, PhD ’21, and four others.

    For many years, researchers have assumed that the key to the ancient concrete’s durability was based on one ingredient: pozzolanic material such as volcanic ash from the area of Pozzuoli, on the Bay of Naples. This specific kind of ash was even shipped all across the vast Roman empire to be used in construction, and was described as a key ingredient for concrete in accounts by architects and historians at the time.

    Under closer examination, these ancient samples also contain small, distinctive, millimeter-scale bright white mineral features, which have been long recognized as a ubiquitous component of Roman concretes. These white chunks, often referred to as “lime clasts,” originate from lime, another key component of the ancient concrete mix. “Ever since I first began working with ancient Roman concrete, I’ve always been fascinated by these features,” says Masic. “These are not found in modern concrete formulations, so why are they present in these ancient materials?”

    Previously disregarded as merely evidence of sloppy mixing practices, or poor-quality raw materials, the new study suggests that these tiny lime clasts gave the concrete a previously unrecognized self-healing capability. “The idea that the presence of these lime clasts was simply attributed to low quality control always bothered me,” says Masic. “If the Romans put so much effort into making an outstanding construction material, following all of the detailed recipes that had been optimized over the course of many centuries, why would they put so little effort into ensuring the production of a well-mixed final product? There has to be more to this story.”

    Upon further characterization of these lime clasts, using high-resolution multiscale imaging and chemical mapping techniques pioneered in Masic’s research lab, the researchers gained new insights into the potential functionality of these lime clasts.

    Historically, it had been assumed that when lime was incorporated into Roman concrete, it was first combined with water to form a highly reactive paste-like material, in a process known as slaking. But this process alone could not account for the presence of the lime clasts. Masic wondered: “Was it possible that the Romans might have actually directly used lime in its more reactive form, known as quicklime?”

    Studying samples of this ancient concrete, he and his team determined that the white inclusions were, indeed, made out of various forms of calcium carbonate. And spectroscopic examination provided clues that these had been formed at extreme temperatures, as would be expected from the exothermic reaction produced by using quicklime instead of, or in addition to, the slaked lime in the mixture. Hot mixing, the team has now concluded, was actually the key to the super-durable nature.

    Impressive.

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    Post  Begome Wed Jan 25, 2023 8:36 pm

    Hey kvs,

    have you heard of the "Dark Comets hypothesis" by Rob Sheldon? (Comets, Water and Big Bang Nucleosynthesis ... I recommend skipping the Introduction and section III as they're a bit esoteric IMO).

    So basically certain properties of the very early universe in the electro-weak era make it electrically conductive and lead to strong primordial magnetic fields, which then discharge into the universe as they later collapse due to the end of that era when nucleosynthesis begins, thus providing more energy for nucleosynthesis, which can thus proceed to produce elements far past Li, even O, which means water (or ice), which means gigantic ice balls due to condensation and freezing, which gives much earlier galaxies (as confirmed now by JWST) and basically does away with the need for Dark Energy and Dark Matter.
    The "dark matter" would simply be comets, which have been shown to have fairly low albedo and would sit in "halo clouds" around galaxies, just as dark matter is expected to by the mainstream; the reason they behave so differently than "non-comet matter" is because comets effectively are matter with its own rocket engine that starts up whenever it either gets big enough or comes near a heat source and thus as a whole has a lot less viscosity and resists this disk-like accretion seen with other matter.

    The author claims that this could solve multiple problems with the mainstream version of standard cosmology, such as CEMP stars, cold white dwarfs, (too) early galaxy formation, matter-antimatter imbalance, missing dark matter and several others.

    Thoughts?
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    Post  kvs Wed Jan 25, 2023 10:33 pm

    I think that the line of investigation of this paper is very interesting and this is the sort of research that astrophysics needs. Not
    groupthink, circle-jerk big ego affirmation.

    But I do not think there is an "either/or" situation here. In my view dark matter is the simple failure to recognize that gravity is nonlinear
    and not Newtonian. That is, the gravitational "constant" G is a function of the mass distribution. The MOND correction is basically
    the same premise since we have a G(r) which then gives a deviation from the 1/r^2 force law.

    The reason for the nonlinearity is that gravitons self-interact. We see this effect in the strong force since gluons self-interact and we
    get asymptotic freedom near the force center but increasing attraction away from it (Yang-Mills potential). Gravity does not have the same
    dramatic amplification of the force away from masses as quarks have with the strong force. But it is enough to give us the galaxy rotation
    curves without appealing to missing mass. This is not to say that there is no mass that we do not see. So a comet halo instead of a dark
    matter halo is still possible but the bottom line is that Newtonian theory is only a weak field approximation.

    It is funny that galaxy dynamics simulations use Newton's law of gravity. They do not use GR equations and do not even use "retarded" potentials
    assuming a speed of light gravity. A weak field approximation of GR should be used for galaxies. But GR is not sufficient since it assumes a
    constant G as the whole theory rests on Newton's law. We simply to not have strong field limit understanding of gravity. Black holes are not
    examples of such understanding since GR does not have the strong field limit gravity as its base. In other words, black holes are mathematical
    constructs from some theory and not reality. GR should be formulated starting from a variable G framework.

    In cosmology, having a variable G gets around the ludicrous, ad hoc "hyperinflation" hack. There are too many such deus ex machina fixes
    in astrophysics and cosmology.

    Anyway, we are too far away from full understanding of reality regardless of the tone put out by "authorities" in various scientific subjects.

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    Post  Begome Wed Jan 25, 2023 11:21 pm

    Thank you for your response! I agree that there are a lot of dogmas in science that quench innovative research and get people fired for questioning them. I also agree that it's not either this or MOND, for example, but I'd like to point out that the paper does comment on some of the points you brought up:

    First, the author also proposes that in his theory this inflaton field, which I think is what you're referring to with hyperinflation, is not necessary, because the discharge from the primordial magnetic field "means that the transition from electroweak to nucleosynthesis era is a first order phase transition [...] mapping the coherence of the field onto the coherence of the matter." and thus "the universe achieves a uniform temperature and density that is reflected in the CMBR, without the need for a global inflaton field. Or more precisely, the global magnetic field provides the coherence that was previously attributed to the global inflaton field (albeit indirectly)." (both quotes are from the paper I linked, section 2.4, which also talks about how this theory fixes the "flatness problem" of the Big Bang).

    As to MOND, he writes "Even the unorthodox modified newtonian dynamics/gravity (MOND) has not worked for all galaxy types, leaving theorists without a viable DM candidate (Joyce et al., 2015)." and also, that as a consequence of the way the "comet matter" interacts with the "non-comet matter", its density will decrease around accumulations of matter of higher acceleration without the need for MOND (see section 2.1).

    I do hope that this idea is looked into more in the future, as I personally really like it (Gen. 1:2  Very Happy  ).

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    Post  nomadski Sun Jan 29, 2023 9:56 am

    A question about quantum effect in double-slit experiment . In my view , considering hard determinism , any human  observer phenomenon must necessarily follow an event . Logically , it is impossible to obtain a perception , before an event ? Our actions are therefore a result , not of our thoughts of perceptions , but they are reverse , determined externally and entirely without our participation . The mistake that is made , because our perceptions follow very quickly ( or slowly by photon standards ) the event , is to confuse the two ! Our perceptions are time dependent .

    What if this is also true , from the perspective of the photon , travelling towards a slit . Since no human perception is possible before the event ,  the photon must really be " seeing " the human observing the slit , before the human has decided to move into position ! And after it  moved in said direction itself . But the human observer " thinking of  deciding , " days in advance , to observe , means that this event reacted and then  observed from photon perspective , has occurred almost instantly and it's entirety , during it's transit towards the slit ! Do objects travelling at light speed , have different perception of passage of events ? Do photons " see , " and react involuntarily like bigger objects like humans ?
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    Post  kvs Sun Jan 29, 2023 6:57 pm

    I think the best physical interpretation so far for quantum mechanics is from pilot wave effects. All of the key features of QM can
    be captured in classical fluids when a test particle is subjected to the action of its own wake and that of others:

    https://news.mit.edu/2014/fluid-systems-quantum-mechanics-0912

    Photons and particles are no just passing through a coordinate map, they pass through a material entity called space (time is not a dimension
    so space-time is not fundamental). That there would be wave-like effects of the space fabric is manifestly plausible.

    BTW, the Copenhagen consensus on the interpretation of QM is total BS. The observer and all other systems are quantum entangled.
    The idea of an observer collapsing a wave-function by observation as some sort of deus ex machina entity is ludicrous and not even based
    on QM. The observer is part of any quantum system. QM is afflicted with too much philosophizing which somehow forms a groupthink.

    This observer-wave-function collapse view is also subjectivist at its core. Somehow the observer creates reality by merely observing.
    Obvious nonsense which has been sanctified by collective parroting. So called Einstein-Rosen-Podolsky paradox is really nothing since
    no information flows from the observation of the state of one member of an entangled pair of particles (or whatnot) to the other. The
    observer does not set the state he only observes it. The double slit experiment does not contradict my point, since the attempt to
    measure the location of the photon (or particle) traversing the slits totally disrupts the pilot wave environment. The observer does not
    create the state of any system through observation.

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    Post  kvs Sun Jan 29, 2023 7:41 pm

    This is a show stopper paper in GR, but one which will be ignored:

    https://arxiv.org/abs/2101.02012

    The above paper demonstrates that the interior solution of a spherical fluid (i.e. mass) shell is not flat like in Newtonian theory.
    The derivation cannot be challenged and the authors point out that if you use a potential that deviates from 1/r in Newton's theory
    then the gravity does not cancel out in a spherical shell interior either and actually has similar "repulsive" properties near r = 0.

    Note figures 2 and 4. The metric time and radius prefactors change sign in the interior just like they do in the classical Schwarzschild
    (or more accurately Hilbert) solution, aka static black hole solution.

    1) It is routine to claim that spherical mass shells in GR behave just like Newtonian ones and that there is no potential in the interior.
    This is pure hackery that is practiced by "authorities" in the field. They are all pathetically sloppy with doing the math. Math is
    not optional even in physics. GR is based on a set of equations and not just "intuition". If you can't do boundary conditions right,
    then GTFO.

    2) It is a dogma that the interior black hole solution has time and radius changing roles. This is patent BS since there is no law or
    constraint in solving Einstein's equations that requires the sign of a prefector to stay the same. The thing that matters is the geodesics
    that are described by the metric. The BH interior solution gives physical geodesics.

    3) The key detail is that motion along static BH geodesics in the exterior solution equals the speed of light at the event horizon. So any
    attempt to continue them into the interior violates the speed of light limit. You have attempts to "prove" that these exterior geodesics
    cross the horizon and go to r=0. This includes the vaunted Kruskal-Szekeres coordinate transform. This is all BS since such transforms
    do not conserve information (they are not diffeomorphisms). This is neither physics nor mathematics. A straightforward analysis of the
    interior solution shows geodesics with motion towards the event horizon just as with the exterior geodesics. Similarly they also have
    speed of light motion only at the horizon.

    The only physical and mathematical inference is that black "holes" are 2D spherical mass shells at the event horizon.

    The desire for a point mass singularity is pathological and has resulted in a corruption of GR. Einstein's intuition was right on target and
    the clowns that work in his name waited until he died to shove their point mass singularity fetish full bore on the world. They claim that
    so-called BH observations prove the existence of a point mass singularity. There is simply no way to infer a point mass singularity from
    any astrophysical observation. A black shell can produce the same image.

    One of the origins of the point mass fetish stems from the point charge solution in EM. The homogeneous Poisson equation (no charge)
    gives a solution for the point charge. The reason is that the point charge is basically all vacuum so the vacuum system has to have the
    exterior field as one of the solutions. The other is just a no field solution. This thinking was extended to GR and it was assumed that
    there would be a point mass solution as well. But this was a desire and not impartial science. The reality is that there is no point
    mass solution in GR with this approach (i.e. solving the homogeneous system). There is only a 2D mass shell solution. A point mass
    solution requires cranking through the full system of equations with a source term (stress-energy tensor). No free lunch is available.

    For me it is clear that spacetime in GR is an elastic, conservative fabric. So what we see in the mass shell solution is the stretching of
    space near the mass (shell) and compression in the interior. (Note that time acts in the opposite way to the radial space component.)
    In the exterior solution the stretching can spread into an infinite volume. But in the interior it is trapped in a finite volume so it results
    in a compression away from the shell interior surface. There is no cancellation effect which you see in linear Newtonian theory. It is
    singular even for mass shells well beyond the Schwarzshild radius because spacetime deformation has a roughly 1/r dependence. If it
    was 1/r^c where c > 1, then there would be no singularity (in spacetime curvature) at r=0. (This may require c to be big enough and
    for sure c=2 would not produce a divergence).





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    Post  flamming_python Sun Jan 29, 2023 9:03 pm

    The idea that black holes are basically just their shell at the event horizon and that there is no interior as such, is not a new one.
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    Post  kvs Sun Jan 29, 2023 9:09 pm

    But it has been forgotten for unjustified reasons. Science is not about the wants and needs of some personalities.

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    Post  Begome Sun Jan 29, 2023 10:05 pm

    kvs wrote:The double slit experiment does not contradict my point, since the attempt to
    measure the location of the photon (or particle) traversing the slits totally disrupts the pilot wave environment.
    But doesn't the delayed choice quantum eraser experiment show that the pattern change is not due to instrumental interference? It seems to "decouple" what happens at the double slit from the determination of the ability to measure or not measure the original photon path even to the degree that the entangled photon, which impacts the main sensor (where the pattern is recorded over many iterations), does so before the other photon hits the first beam-splitter.
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    Post  kvs Sun Jan 29, 2023 10:53 pm

    This reminds me of all the covid "studies" that are trotted out to claim that vaccines are necessary and that other options are dangerous.

    Comment:

    In this experiment, a single photon is aimed at the double-slit. If it passes through the left slit, it will hit a crystal placed behind the slit on the
    left side of the crystal; if through the right slit, it will hit the crystal on the right side. We will not actually be measuring the interference vel non
    of the incoming photon, but of the subsequently generated photons.

    When the incoming photon hits the crystal, it is destroyed and a pair of entangled photons is generated by the crystal at the spot where it hit.

    Because of entanglement, the properties of the two entangled photons will forever be correlated. Therefore, if we can later identify one of the
    entangled photons as having come from, say, the left side of the crystal, we will thereby know, retroactively, that its twin also came from the left
    side of the crystal, so that we will then know where both entangled photons came from.

    This is not the same as a double slit experiment. Interaction with the crystals is not a conceptual triviality. The two crystals are entangled
    quantum systems added to the double slit with which any photon or electron is entangled as well.

    None of the claims of proof studies for the double slit experiment even start to consider the pilot wave view. There is no way in which to
    measure the "true path" without interfering with the wave function of both the traversing particle and the double slits. The slits may be
    considered classical and an implicit linearization invoked where they are not considered as part of the QM system, but that is just an
    approximation.

    Anyway, the idea that a magical observer creates reality by observing is infantile nonsense. It seems there is a lot of effort to stuff this
    subjectivist garbage down everyone's throat for over 100 years now.
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    Post  kvs Sun Jan 29, 2023 10:55 pm

    Solution for a point mass in GR:

    http://www.m-hikari.com/astp/astp2007/astp1-4-2007/castroASTP1-4-2007.pdf

    (ignore the stupid warning about downloading, the Vixara link is down).

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    Post  Begome Sun Jan 29, 2023 11:42 pm

    kvs wrote:This is not the same as a double slit experiment. Interaction with the crystals is not a conceptual triviality. The two crystals are entangled
    quantum systems added to the double slit with which any photon or electron is entangled as well.
    Sure, but there are still two possible paths the original photon can take (if behaving as a particle...it can also take both simultaneously if behaving as a wave). So call it an analogy of a double slit or something similar rather than another instance of a double slit.

    kvs wrote:Anyway, the idea that a magical observer creates reality by observing is infantile nonsense. It seems there is a lot of effort to stuff this
    subjectivist garbage down everyone's throat for over 100 years now.
    Sure; that interpretation is not obligatory though: one could also say that the possibility of measurement is relevant rather than some subjective "becoming aware of". IIUC, the experiment merely shows that if the first beam-splitter (either BSA or BSB in the diagram of the linked article) reflects the photon then the subsequent measurement will always be correlated with a clumping pattern on the main detector and if it lets the photon pass (50% chance) then it's always correlated with an interference pattern on the main detector (which in both cases records that portion of the pattern before the beam-splitter starts interacting with the entangled photon).
    Since the location of the photon in the original crystal does not matter AFAICT w.r.t. whether BSA/BSB will reflect or let pass the photon it does seem to be a problem for the idea that the pattern is affected by the measurement in a "propagating" way, that is that first there is the event of measurement or no measurement and then the resulting pattern occurs...actually in the experiment the pattern is recorded before the interaction with BSA or BSB.


    Last edited by Begome on Sun Jan 29, 2023 11:49 pm; edited 1 time in total (Reason for editing : clarified further)
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    Post  Begome Mon Jan 30, 2023 1:41 am

    Also, what do you think about the movie "The birth of the Universe" (recent Russian movie that includes the Sky Scholar guy and pushes the Aether theory...though Sky Scholar was not involved in pushing aether)?

    One logical contradiction of the whole aether thing seems to be that they say that it's denser further up in the atmosphere and so it "displaces" the air molecules downwards, explaining the accumulation of air at the surface (since they seem to want to derive gravity from aether density), but then they say that all atoms are actually made of aether, which would include air molecules...seems it's just rank speculation and the whole movie reeks of pantheistic and syncretistic undertones.
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    Post  kvs Fri Feb 10, 2023 2:11 pm



    I guess we now know what super-secret submarine propellers are like. It is one of these ideas that seems so obvious in hindsight.
    Typical propellers based on little wing sections are a primitive first attempt.
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    Post  kvs Fri Feb 10, 2023 2:40 pm

    Also, what do you think about the movie "The birth of the Universe" (recent Russian movie that includes the Sky Scholar guy and pushes the Aether theory...though Sky Scholar was not involved in pushing aether)? One logical contradiction of the whole aether thing seems to be that they say that it's denser further up in the atmosphere and so it "displaces" the air molecules downwards, explaining the accumulation of air at the surface (since they seem to want to derive gravity from aether density), but then they say that all atoms are actually made of aether, which would include air molecules...seems it's just rank speculation and the whole movie reeks of pantheistic and syncretistic undertones. wrote:

    I have not seen this movie.

    I think aether is a failed attempt to ascribe fluid properties to space. Gravity is supposedly then an aether flow.

    That space is material is a fact. It has volume and if GR is to be believed it can also be deformed. Abstracting it as a coordinate
    system does not remove the need for a material medium. The mistake is to try to paint this medium with understanding
    derived from our every day experience such as solids and fluids. The latter are collections of atoms whereas space(-time) seems
    to be some sort of quantum "foam" with granularity at the Planck length scale. The full set of features of this medium are unknown
    and it may have large scale quantum mechanical properties in the sense that the organization is not confined to the Planck scale.
    We have theoretical attempts such as holography (https://en.wikipedia.org/wiki/Holographic_principle).

    I think the speed of light limit is a manifest demonstration of material properties of space. Why the value of "c" that we have
    and not anything else? Why not infinity as in Newtonian theory? The cosmological models that appear more physically plausible
    (e.g. no deus ex machina hyperinflation) are variable "c" theories. It would make sense for the transmission properties of
    the space medium to change with time if there is indeed some sort of Big Bang expansion. But I have some skepticism for
    the Big Bang since it smells like a creation epic. If we had this "initial singularity" then how did we get out of it and what
    if there is an ongoing cycle of Big Bangs at some vast number of points throughout a vastly bigger universe?

    People have a hard time with special relativity because it is corrupted by a subjectivist interpretation. SR flows from
    the Lorentz equations which happen to leave Maxwell's EM equations invariant. Attribution of these properties to Einstein
    and Lorentz is pure wankery. Poincare had the correct interpretation of the Lorentz equations. They are absolute with
    the true rest frame being the medium frame where the photons live. There is no contradiction. The contradiction is in
    Einstein's "relativity" where an implicit "renormalization" is done for every moving observer. This sets up nonsensical
    physical inferences such as the twin's "paradox". The reality is that any moving observer has a Lorentz distorted frame
    even if they can't tell that they are in one. The universe cares about objective reality and all observers and not subjective
    perceptions of some observer. Moving inertial frames do not all have the same geometry as the v=0 frame. They have
    the geometry of v /= 0 frames. Setting v = 0 for every moving observer is BS. With the "absolutivity" interpretation of the
    Lorentz transform there are no more paradoxes (aka logical contradictions).

    GR happens to break relativity. It is a non relational theory and Einstein's attempt to get around this was to fixate on general
    covariance where "no coordinate system is special". But coordinate freedom has nothing to do with relativity. The solution is
    for a global space-time which does not change depending on how fast some observer moves. General covariance is clearly valid
    but it has allowed scum to introduce backdoor nonsense. Only diffeomorphic transformations make physical sense since they
    preserve information. (No points being mapped to lines and planes to lines, etc.) But you will see routine use of non-diffeomorphic
    transforms in GR to "prove" various claims. No coordinate system may be special, but that is not equivalent to "any coordinate
    transform is allowed".
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    Post  kvs Fri Feb 24, 2023 1:00 pm



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    Post  The-thing-next-door Tue Mar 14, 2023 11:48 am

    I just wanted to ask if gamma rays could potentially damage materials such as metals if intensity of gamma ray exposure was sufficiently high.


    I also wanted to ask about weaponising fusion reactions in a sort of beam.
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    Post  kvs Tue Mar 14, 2023 1:51 pm

    http://hps.org/publicinformation/ate/q13412.html

    You need neutron radiation to damage metals.

    https://en.wikipedia.org/wiki/Neutron_embrittlement


    The beam idea would have to be an aperture leak of some sort where high energy neutrons or nuclei are still able to induce fusion.
    Trying to induce fusion in a particle beam far from the source is not realistic since there is no confinement in the beam. You are
    really looking at using fusion in some chamber to generate a high energy beam of daughter particles. The problem with all particle
    beams is that they disperse too fast. People have been trained by sci-fi movies and TV to think that they are practical and better
    than lasers. Using coherent projectiles (rail gun launched if needed) is vastly superior to using a dissipating particle beam.
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    Post  The-thing-next-door Tue Mar 14, 2023 2:55 pm

    What about larger particles or neutral particles? Could those work in an atmosphere?

    The other things I was considering are dust guns and guns that fire waves in space time. Would any of those be effective in an atmosphere like earth's?
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    Post  kvs Sun May 28, 2023 1:48 pm


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    Post  kvs Mon May 29, 2023 5:20 pm



    Nice video going against the groupthink.

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    Post  kvs Sat Sep 16, 2023 6:11 pm

    There is another absurdity in modern physics that shows the corruption.    Anything traveling at the speed of light cannot have any
    dimensional extent along the axis of travel.    So if we ignore the detail that mass cannot travel at the speed of light, a rod of any
    length aligned parallel to its axis of travel will appear to have zero length if its speed is that of light.   So how can a photon have a
    spatially extended wavelength?   Even if it actually is a localized wave to us it would appear to have no spatial extent along its axis
    of motion.   Just apply the Lorentz transform to any wave packet to see this.

    A sane explanation would be that photon "waves" are intrinsic and do not transform like objects composed of atoms via the Lorentz
    equations.   These quantized waves are a demonstration of the existence of a space medium.   Much like water waves exist because
    there is a body of water to sustain them.   Of course, the EM waves are not subject to the same equations as the water waves.  

    So there is no "irregular" photon frame which is a good indication that the concept of frames for moving objects is BS.   There is only
    one frame and all objects with any motion and EM waves exist in this frame.   The frame of the universe and ultimately the absolute
    rest frame.   Photons and EM waves propagate in this frame supported by the material entity known as space.   There is no partition
    of reality into different physical realms based on relative motion.   No BS paradoxes are possible since any Lorentz deformation of moving
    objects is intrinsic and relative to the absolute rest frame and not relative to each other.

    If you move with v increasing to c, you would still see light moving at the speed of light.   That is the nature of reality as reflected in
    the Lorentz transform (a conservation property of Maxwell's equations).   Moving observers are distorted in manner that "hides" their
    motion from themselves.  They cannot measure their own Lorentz distortion.   All they can perceive is differences in the Lorentz distortion
    of other objects.

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    Post  GarryB Sun Sep 17, 2023 4:15 am

    It is funny.... I always took the consequences of reaching the speed of light... zero dimension in the direction of travel... essentially becoming a 2D object, achieving infinite mass and for time, as measured on board the object or craft to stop... as being that the object ceased to exist in this universe, because a point of infinite mass... even a singularity is supposed to have a mass that is measurable and an infinite mass would not be measurable and although the effect of gravity covers the entire space time it rapidly diminishes to a rather small force over not a particularly great distance... the effect of Jupiter for instance will effect the earth but not people on the Earth to a degree that they would notice.

    By closing your eyes you can't identify the direction the sun is just by feel... even through the planet... by its gravity. You can't even feel the gravity of the moon even if its pull is reflected in the tides on earth.

    So an object of infinite mass that is 2 dimensional for which time has stopped... add that all up... does that mean it pops out of existence in this space time and goes somewhere else?

    Is that what hyperspace is supposed to be in sci fi?

    Of course there are other funky things like electrons in the shells of atoms... from what I have read and understood electrons can't exist between the shells, and so when they move from one shell to the other or get lost and become free electrons they do so without ever being in the gaps between the shells, though the free electrons must therefore exist outside the outermost shell of atoms so the number of shells must be finite because the relative distance of the shells compared with the size of the electrons and protons and neutrons is enormous if my teachers at school are to be believed. Subatomic particles the size of marbles lead to electron shells kilometres wide... they are mostly empty space... so how far to the shells for any given nucleus extend and is it related to the mass of the nucleus... so a Hydrogen atom with just one proton can only have one shell for instance...

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